Microsurgical instruments

ABSTRACT

A surgical instrument may include a housing, a first actuation member configured; a coupler operatively connected to the first actuation member for imparting a reciprocating action to a portion of the instrument, a second actuation member configured for imparting a rotational action to a portion of the instrument, a first cannula operatively connected to the second actuation member, such that the first cannula is configured for rotational movement with respect to the housing, and a wire member at least partially disposed within the first cannula and fixed to the coupler, the wire member configured to rotate and reciprocate with the coupler.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of U.S. application Ser. No.14/215,284 filed Mar. 17, 2014, now published as US 2014/0277046, which,in turn, claims the benefit of U.S. provisional application Ser. No.61/790,679 filed Mar. 15, 2013, the disclosures of which are herebyincorporated in their entirety by reference herein.

TECHNICAL FIELD

The present disclosure relates to surgical instruments that may be usedfor microsurgical procedures.

BACKGROUND

Microsurgery is a surgical technique for operating on minute structureswhich require magnification to see the detail of the anatomy, withspecialized, miniaturized precision instruments. Microsurgery permitsoperations that were once virtually impossible, including, for example,removal of tumors intricately involved with vital eloquent structures ofthe brain. These types of procedures require safely cutting ormanipulating certain structures to cut, move or hold them during aprocedure without damaging them or collateral tissues. Due to thedelicate nature of the structures involved, the design of suitablesurgical instruments for these types of procedures presents certainchallenges.

For example, because the need to create a narrow and often deep surgicalcorridor to access the structures being subject to the operation are inthe same focal corridor and surgical site. Often these tissues aredifficult to differentiate the normal from the abnormal tissue, manyknown surgical device have line of sight issues whereby the shaft and/orthe effector end of the instrument is very difficult to observe during aprocedure without also occluding the surgeons view of the surgical site.As a result, users are often required to hold the instrument at awkwardangles so as to maintain visibility during the procedure, which may leadto unintended movements by the operator causing harm to normal tissues.Often because of the size and angle at which the instrument must beentered into the surgical site, the actual use of the instrument blocksthe surgeons view of the surgical site during its use and the surgeoneffectively uses the instrument “blindly” and removes the instrumentfrom the surgical field so as to inspect the outcome of the use of theinstrument. If unsatisfactory, then the instrument is then placed againin the surgical field for additional work. This can often go on formultiple passes the surgical site. Such repeated action can cause damageto the tissues which line the surgical corridor due to the bumping ofthe instrument as they are passed in and out, this results in proceduralinefficiency as well as increased surgeon fatigue.

Manipulation of the microsurgical device is also difficult within thesurgical field. For example, while a device may be configured to cuttissue or grasp different structures, often there is no mechanism tochange angles of orientation of the effector end of the device duringthe cutting or grasping operation while it is in use within the surgicalsite. In cases where these accommodations have been made to aninstrument they have been created for use with endoscopic imaging andnot been designed for use with microscopic or exoscopic imagingmodalities. Accordingly, the user has traditionally been required toextract the device from the surgical field to reposition the device forfurther operation or remove the device and request that a differentangled device be provided. This action thus lengthens a procedure.Moreover, depending on the set up in the operating suite, in someinstances the repositioned angle requires the user to hold and operatethe device in an awkward manner, also leading to fatigue and anunintended impact to the tissues within the surgical site.

Based on the foregoing, an improved device that allows for easymanipulation for both line of sight issues, as well as to permitflexibility of use during a procedure.

SUMMARY

A surgical instrument may include a housing, a first actuation memberconfigured; a coupler operatively connected to the first actuationmember for imparting a reciprocating action to a portion of theinstrument, a second actuation member configured for imparting arotational action to a portion of the instrument, a first cannulaoperatively connected to the second actuation member, such that thefirst cannula is configured for rotational movement with respect to thehousing, and a wire member at least partially disposed within the firstcannula and fixed to the coupler, the wire member configured to rotateand reciprocate with the coupler.

A surgical instrument may include a housing, a first actuation memberconfigured for imparting a reciprocating action to a wire member, asecond actuation member configured for imparting a rotational action toa first cannula, a cap member arranged at a distal end of the firstcannula, wherein the cap member a slot configured to receive a blade,and wherein reciprocation of the wire member causes the blade to movetransversely across the slot to sever tissue elements.

BRIEF DESCRIPTION OF THE DRAWINGS

Exemplary embodiments of the present disclosure will now be described ingreater detail with reference to the attached figures, in which:

FIG. 1 is a cross-sectional view of a first exemplary embodiment of amicrosurgical instrument;

FIG. 2 is an enlarged view of area 2 taken from FIG. 1;

FIG. 3 is an enlarged view of area 3 taken from FIG. 1, with an outercannula removed for clarity;

FIG. 4 is a perspective view of area 3 taken from FIG. 1;

FIG. 5 is an enlarged perspective view of area 4 taken from FIG. 1;

FIG. 6 is an enlarged cross-sectional view of an actuation mechanism;

FIG. 7 is an elevational view of a second exemplary embodiment of amicrosurgical instrument;

FIG. 8 is a cross-sectional view of the microsurgical instrument of FIG.7;

FIG. 9 an enlarged perspective view of area 8 taken from FIG. 8;

FIG. 10 is an enlarged cross-sectional view of area 10 of themicrosurgical instrument of FIG. 8;

FIG. 11 is an enlarged cross-sectional view of area 10 taken from FIG.8;

FIG. 12 is a perspective view of a distal end of an alternativearrangement for a surgical device;

FIG. 13 is a cross-sectional view of the surgical device of FIG. 12; and

FIG. 14 is a cross-section view of the surgical device of FIG. 12 takenalong lines 14-14 in FIG. 13;

FIG. 15 is a partial cross-sectional view of an alternativemicrosurgical instrument;

FIG. 16 is a perspective view of a distal end of the microsurgicalinstrument of FIG. 15;

FIG. 17 is a further perspective view of the distal end of themicrosurgical instrument of FIG. 15.

FIG. 18 is a perspective view of an outer cannula used with analternative distal end of a microsurgical instrument of FIG. 15;

FIG. 19 is a perspective view of an inner cannula used with the outercannula of FIG. 18.

FIG. 20 is an enlarged elevational view of a distal end of amicrosurgical device that illustrates the interaction of the inner andouter cannulas of FIGS. 18 and 19.

FIG. 21 is an elevational view of another exemplary embodiment of amicrosurgical instrument.

FIG. 22 is a perspective cross-sectional view of the microsurgicalinstrument of FIG. 21.

FIG. 23 is a cross-sectional view of the microsurgical instrument ofFIGS. 21 and 22.

FIG. 24 is a perspective view of an outer cannula distal end of FIG. 21.

FIG. 25 is another perspective view of an outer cannula distal end ofFIG. 21.

FIG. 26 is another perspective view of an outer cannula distal end ofFIG. 21.

FIG. 27 is cross-sectional view of an outer cannula distal end of FIG.24.

DETAILED DESCRIPTION

As required, detailed embodiments of the present invention are disclosedherein; however, it is to be understood that the disclosed embodimentsare merely exemplary of the invention that may be embodied in variousand alternative forms. The figures are not necessarily to scale; somefeatures may be exaggerated or minimized to show details of particularcomponents. Therefore, specific structural and functional detailsdisclosed herein are not to be interpreted as limiting, but merely as arepresentative basis for teaching one skilled in the art to variouslyemploy the present invention.

Referring now to the discussion that follows and also to the drawings,illustrative approaches to the disclosed instruments and methods areshown in detail. Although the drawings represent some possibleapproaches, the drawings are not necessarily to scale and certainfeatures may be exaggerated, removed, or partially sectioned to betterillustrate and explain the present disclosure. Further, the descriptionsset forth herein are not intended to be exhaustive or otherwise limit orrestrict the claims to the precise forms and configurations shown in thedrawings and disclosed in the following detailed description.

Described herein are microsurgical instruments that are configured formicrosurgical operations, such as vascular procedures. The microsurgicalinstruments are particularly suited for minimally invasive surgicalprocedures that are performed through a port, such as that which isdisclosed in U.S. patent application Ser. No. 13/280,015, the contentsof which are incorporated in its entirety.

Referring to FIG. 1, a first exemplary configuration of a microsurgicalinstrument 100 will be described. Microsurgical instrument 100 comprisesa handpiece, 102, a first actuation mechanism 104, a second actuationmechanism 106, an inner cannula 108 (best seen in FIGS. 3-5), an outercannula 110, and a center wire 112. The handpiece 102 may be generallyelongate, as shown in FIG. 1. A proximal end 114 may curve downwardly todefine a grip section.

The outer cannula 110 is defined by a distal end 116 and a proximal end118 (best seen in FIG. 2). The proximal end 118 is non-rotatably fixedwithin a channel of the handpiece 102. In one exemplary configuration,the channel 119 extends from a distal end of the handpiece 102 to acavity 130 formed in the handpiece 102.

In one exemplary configuration, outer cannula 110 includes an offsetbend (as illustrated in FIG. 1). The offset bend allows for a clear lineof sight during the procedure which is useful for delicate procedures.In another exemplary configuration, the outer cannula 110 may beconstructed of a suitable material that is selectively malleable suchthat the outer cannula 110 may be bent to a desired location, but oncebent will maintain its position.

The inner cannula 108 is received within the outer cannula 110. Theinner cannula 108 is fixed to the second actuation member 106. Forexample, a proximal end 121 of the inner cannula may be operativelyfixed to the second actuation member 106. In one exemplaryconfiguration, the second actuation member 106 is configured as arotation wheel. Thus, when rotation wheel 106 is rotated, inner cannula108 will also rotate. A distal end 123 of the inner cannula 108 mayinclude a key way 120, as best seen in FIG. 4. In one exemplaryarrangement, key way 120 is configured to receive a suitable materialthat has sufficient rigidity to receive an opposing cutting bladematerial without dulling a blade (as will be explained in further detailbelow). Some examples of suitable material include, but are not limitedto, an epoxy resin or thermoplastic resin. In one exemplaryconfiguration, the key way 120 may be insert molded with a resin to forma cut block at the distal end of inner cannula 108.

Inner cannula 108 also defines an opening 122 that is positionedadjacent the distal end 123, as will be discussed in further detailbelow. The inner cannula 108 may include one or more relief cut-outs 124(best shown in FIG. 3) to allow for flexibility of the inner cannula 108while still providing for columnar strength. The distal end 123 of theinner cannula 108 may be configured with a reduced profile for ease ofmanipulation in narrow surgical corridors, as well as providing increasefield of vision. In one exemplary configuration, the distal end 123 isdefined by generally opposing planar lateral surfaces 125 that arepositioned inboard of an outer periphery of the inner cannula 108, on aportion of the inner cannula 108 that protrudes from outer cannula 110.The reduced profile section further includes an inclined portion 127that includes the opening 122. The distal end 123 of the inner cannula108 includes a toe portion 129 that serves as a cut block, as will beexplained in further detail below.

The center wire 112 is positioned within the inner cannula 108. Whilenot specifically shown, the center wire 112 may also include one or morerelief cut-outs, similar to cut-outs 124 for the inner cannula 108, toallow for flexibility while providing columnar strength. The center wire112 includes a cutting edge 131 on a distal end 133 thereof. A proximalend 135 of the center wire 112 is fixed to a coupling member 128 (bestshown in FIG. 2). Coupling member 128 includes a gear mechanism 132attached thereto. The coupling member 128 is partially disposed in thecavity 130 of the handpiece 102. The gear mechanism 132 is disposedwithin a slot 134 that is in communication with the cavity 130. The slot134 opens through part of the handpiece 102, as will be discussed infurther detail below.

The cavity 130 formed within the handpiece 102 includes severalsections. A first section 130 a is configured to receive hub member 126,such that once hub member 126 is disposed within the first section 130a, hub member 126 may not be easily removed from handpiece 102. In oneexemplary arrangement, at least a portion of the handpiece is separablefrom a remaining portion, such that the hub member 126 may be positionedwithin the first section 130 a. Once positioned, the handpiece isassembled and fixedly secured together to trap the hub member 126 withinthe first section 130 a. In another exemplary arrangement, the hubmember 126 may be made of a compliant material having some memory thatmay be selectively deformed as hub member 126 is press-fit into thefirst portion 130 a. Once the hub member 126 enters the portion 130 a ofthe cavity, the hub member 126 will return to its original shape,thereby being trapped within the first portion 130 a.

Cavity 130 further includes a second portion 130 b and a second portion103 c. Second portion 130 b joins first portion 103 a and third portion130 c. Third portion 130 c is sized to receive rotation wheel 106 and isthus larger than second portion 130 b. Third portion 130 c extends intoan extension member 135 that extends outwardly from an outer peripheryof handpiece 102.

Rotation wheel 106 is mounted to hub member 126 by a web 136. Details ofthe hub member 126 may be best seen in FIG. 6. The hub member 126 ispositioned within the first cavity portion 130 a of handpiece 102. Achannel 138 extends through the hub member 126 and opens into a cavity140 formed by the web 136 and rotation wheel 106. The inner cannula 108is fixed within the channel 138 of the hub member 126 such that theinner cannula 108 rotates with the rotation wheel 106. A distal end 142of coupling member 128 is received within the cavity 140. In oneexemplary arrangement, the coupling member 128 is configured toselectively slide within the cavity 140, relative to the rotation wheel106, as will be explained in further detail below.

Hub member 126, rotation wheel 106 and coupling member 128 arepositioned within cavity 130 formed within a distal portion of handle102, as best shown in FIG. 2. A portion of rotation wheel 106 extendsoutwardly from a portion of the handpiece 102. A remaining portion ofthe rotation wheel 106 is disposed within the third portion of thecavity 130 c. First actuation member 104 is operatively engaged to gearmechanism 132.

More specifically, in one exemplary arrangement, the first actuationmember 104 is configured as a lever and includes teeth members 142disposed on a distal end 144 that are configured to operatively engagegear 132 formed on the coupling member 128. The teeth members 142 extendthrough an opening of the handpiece 102 that is in communication withslot 134. The gear 132 of the coupling member 128 is disposed within theslot 143.

A depression 137 extends proximally from the slot 143 within thehandpiece 102. The depression 137 is configured to receive an extensionmember 139 of the coupling member 128. More specifically, the extensionmember 139 is disposed proximally of the gear 132 and is configured tobe at least partially disposed within the depression 137 to maintain thecoupling member 128 within the slot 134 of the handpiece 102.

First actuation member 104 is pivotally attached to a portion of handle102 such that it is adjacent to rotation wheel 106. In one exemplaryconfiguration, a torsional spring (not shown) may be engaged at a pivotpoint A to bias first actuation member 104 into a ready position, namelya position whereby a proximal end 146 of the first actuation member 104biased upwardly from an outer surface of handpiece 102. Alternatively, acoil spring (not shown) may be disposed within the cavity 130 to biasthe first actuation member 104. When the first actuation member 104 isactivated against a biasing force F created by the spring, center wire112 may be advanced forward to traverse the opening 122 in the innercannula 108. More specifically, actuation of the first actuation member104 will cause coupling member 128 to slide forward within the cavity140 formed by the web 136 and rotation wheel 106. Because a proximal endof the center wire 112 is fixedly connected to the coupling member 128,as the coupling member 128 moves, center wire 112 will also move.

Further, to maintain the orientation of the cutting edge 131 of thecenter wire 112 with respect to the inner cannula 108, the distal end142 of the coupling member 128 and the rotation wheel 106 maybeoperatively connected together with a splined connection. In anotherexemplary arrangement, the distal end 142 may be a hexagonalcross-section that cooperates with a mating hexagonal opening formedthrough the rotation wheel 106. Other cross-sectional shapes withcorresponding mating openings are also contemplated. With thisconfiguration, center wire 112 is rotationally fixed with the rotationwheel 106 such that as rotation wheel 106 rotates, center wire 112 willalso rotate. However, the splined or other mated connection will enablecenter wire 112 is slide axially independent of the rotation wheel 106.

As the first actuation member 104 is depressed, the center wire 112traverses the opening 122. Any tissue or vessels that are positionedwithin the opening 122 as center wire 112 is traversed across will becut. A full depression of the first actuation member 104 will cause thecutting edge 131 to engage against the cut block. However, because thecut block is constructed out of material that is compliant, suchengagement will not serve to damage the cutting edge 131. Continueddepression of first actuation member 104 will maintain the cutting edge131 center wire 112 against the cut block. This action may be desiredwhen withdrawing the instrument 100 from a surgical site so as not tounintentionally rake the opening 122 against tissue. It may also bedesirable to have the cutting edge 131 in engagement with the cut blockwhen rotation of the distal end 123 of the inner cannula 108 is desired.

Because the first actuation mechanism 104 is positioned adjacent thesecond actuation mechanism 106, a user can actuate the center wire 112and rotate the inner cannula 108 using the same hand. By way of exampleonly, the user's hand may be wrapped around a portion of the handle 102of the instrument 100, with a thumb engaging the proximal end 146 of thefirst actuation member 104. A finger of the same hand as the thumb mayengage the second actuation member 106. By only requiring a single handto achieve both axial movement of the center wire 112 and rotation ofthe inner cannula 108, easier manipulation of the instrument 100 may beachieved, without requiring the user to reposition his or her hand inawkward positions. This configuration also allows for reduced visibilityconcerns, as an optimal site line may be chosen by the user, withoutrequiring the user to manually rotate the entire device to achieve adesired cutting operation. Further, because the first and secondactuation members 104, 106 may be easily activated with a single hand,the second hand is free to handle other surgical instruments such as anaspirator or irrigation mechanism that may be needed in a surgicalprocedure.

Another exemplary embodiment is illustrated in FIGS. 7-11. Microsurgicalinstrument 200 is similar to microsurgical instrument 100. Microsurgicalinstrument 200 comprises a handpiece 202, a first actuation mechanism204, a second actuation mechanism 206, an inner cannula 208, an outercannula 210, and a center wire 212. The handpiece 202 may be generallyelongate, as shown in FIG. 8. A proximal end 214 may curve downwardly todefine a grip section.

The outer cannula 210 is defined by a distal end 216 and a proximal end218 (best seen in FIG. 10). The proximal end 218 is non-rotatably fixedwithin a channel of the handpiece 202, as shown in FIG. 10, similar tothe configuration shown with respect to instrument 100. The channel mayextend from a distal end of the handpiece 102 to a cavity 230 formed inthe handpiece 102. In one exemplary configuration, outer cannula 210includes an offset bend (as illustrated in FIGS. 7-8) that allows for aclear line of sight during the procedure. In another exemplaryconfiguration, the outer cannula 210 is configured to be selectivelymalleable such that the outer cannula 210 may be bent to a desiredconfiguration, but once bent will maintain its position.

The inner cannula 208 is received within the outer cannula 210. Theinner cannula 208 includes a proximal end 209 that is operativelyconnected to the second actuation member 206. In one exemplaryconfiguration, the second actuation member 206 is configured as arotation wheel. Thus, when rotation wheel 206 is rotated, inner cannula208 also rotates. In one exemplary arrangement, inner cannula 208 isfixed to a coupling mechanism 228 disposed within the handpiece 202, aswill be described below in greater detail.

In one exemplary arrangement, at a distal end 219 of the inner cannula208, an end cap portion 220 is mounted. End cap portion 220 fixedlycarries a first jaw member 221. First jaw member 221 may further includea textured gripping surface 223 that is configured to grasp tissue orother structures. In one exemplary arrangement, gripping surface 223 isconfigured as a series of alternating grooves and ridges. However, it isunderstood that other textured surfaces are within the scope of thisdisclosure. In one exemplary configuration, end cap portion 220 furthercomprises a retaining mount 225. Retaining mount 225 is configured toreceive center wire 212 therein such that a distal end 227 of centerwire 212 is fixedly secured to the end cap portion 220. While not shown,a distal bottom edge of cap portion 220 may be rounded to eliminate anysharp corners that may damage tissue or other structures.

While not shown, inner cannula 208 may include one or more reliefcut-outs similar to relief cut-outs depicted in FIG. 3 with respect tomicrosurgical instrument 100. The relief cut-outs allow for flexibilityof the inner cannula 208, while providing for columnar strength, therebypermitting selective bending of the instrument 200 to a desiredconfiguration.

A second jaw member 229 is carried on a sleeve member 231. Sleeve member231 is slidably disposed about center wire 212 and fixedly secured tothe distal end 219 of the inner cannula 208. Thus, the second jaw member229 is operatively connected to the inner cannula 208 such that thesecond jaw member 229 is rotationally fixed with respect to the innercannula 208. Second jaw member 229 may be provided with a texturedgripping surface 233 that is oriented in opposing relationship withgripping surface 223, as shown in FIG. 11.

In one exemplary arrangement, the profile of second jaw member 229 issized to be smaller than the first jaw member 221 to provide increasedvisibility. For example, as best seen in FIG. 9, in one arrangement,first jaw member 221 may be provided with a width W₁ that may be sizedto be wider than a width W₂ of second jaw member 229. In yet anotherexemplary arrangement, the first jaw member 221 may be provided with aheight H₁ that is greater than a height H₂ of the second jaw member 229.

The center wire 212 is positioned within the inner cannula 208. Muchlike the arrangement of microsurgical instrument 100 depicted in FIG. 3,the center wire 212 may include one or more relief cut-outs to allow forflexibility while providing for columnar strength, similar to thoseshown with respect to relieve cut-outs 125 of inner cannula 108.

A proximal end 232 of the center wire 212 extends through couplingmember 228. Coupling member 228 includes a gear mechanism 234 attachedthereto, much like the arrangement in instrument 100. The couplingmember 228 is partially disposed within the cavity 230 of the handpiece202. The gear mechanism 234 is disposed within a slot 236 that is incommunication with the cavity 230. The slot 236 opens through part ofthe handpiece 202, as will be explained in further detail below.

The coupling member 228 further includes an extension element 239 thatextends proximally from the gear mechanism 234. A hub element 235 isreceived within the extension element 239 so as to fix the hub element235 to the coupling member 228. The proximal end 232 of the central wire212 extends into the hub element 235 and is fixed connected thereto. Thehub 235 serves to facilitate rotation of center wire 212, as will beexplained in further detail below.

Much like cavity 130, cavity 230 formed within the handpiece 102includes several sections. A first section 230 a is configured toreceive a hub member 226, such that once hub member 226 is disposedwithin the first section 230 a, hub member 226 may not be easily removedfrom handpiece 102. Hub member 226 has a similar configuration as hubmember 126 of instrument 100. In one exemplary arrangement, at least aportion of the handpiece 202 may be separable from a remaining portion,such that the hub member 226 may be positioned within the first section230 a when the two portions of the handpiece 202 are separated. Oncepositioned, the handpiece 202 is assembled and fixedly secured togetherto trap the hub member 226 within the first section 230 a. In anotherexemplary arrangement, the hub member 226 may be made of a compliantmaterial having some memory that may be selectively deformed as hubmember 226 is press-fit into the first portion 230 a. Once the hubmember 226 enters the portion 230 a of the cavity 530, the hub member226 will return to its original shape, thereby being trapped within thefirst portion 230 a.

Cavity 230 further includes a second portion 230 b and a second portion230 c. Second portion 230 b joins first portion 203 a and third portion230 c. Third portion 230 c is sized to receive rotation wheel 206 and isthus larger than second portion 230 b. Third portion 230 c extends intoan extension member 237 that extends outwardly from an outer peripheryof handpiece 202.

Rotation wheel 206 is mounted to hub member 226 by a web 240. A channelextends through the hub member 226 and opens into slot 236 in similarfashion as the instrument 100. The inner cannula 208 extends through thehub member 226 and has a proximal end 209 that is fixedly secured withina distal extension element 242 of the coupling member 228. The distalextension element 242 of the coupling member 228 is fixedly connected tothe rotation wheel 206. Accordingly, the inner cannula 208 isoperatively connected to the rotation wheel 206 such that rotation ofthe rotation wheel 206 causes the coupling member 228 to rotate, therebyrotating the inner cannula 208. Moreover, because the hub element 235 isfixedly connected to the proximal extension element 239, as the rotationwheel rotates the coupling member 228, the hub element 235 will alsorotate. This action causes the center wire 212 to rotate. Furtherbecause both the inner cannula 208 and the center wire 212 are bothconnected to the coupling member 228, the inner cannula 208 and thecenter wire 212 have a fixed rotational relationship. In other words,the inner cannula 208 and the center wire 212 rotate together.

A distal end of the coupling member 208 is received within the cavity ofthe hub 226 in a similar manner as that described above in connectionwith instrument 100. In one exemplary arrangement, the coupling member208 is configured to selectively slide within the cavity relative to therotation wheel 206, as will be explained in further detail below.

Hub member 226 and coupling member 228 are positioned within cavity 230formed within a distal portion of handle 202, as best shown in FIG. 10.A portion of rotation wheel 206 is disposed within the third portion ofcavity 230 c. A remaining portion of the rotation wheel 206 extendsoutwardly from a portion of the handpiece 202. First actuation member204 is operatively engaged to gear mechanism 234.

More specifically, in one exemplary arrangement, the first actuationmember 204 is configured as a lever and includes teeth members 244disposed on a distal end 246 thereof that are configured to engage gear234 formed on the coupling member 228. The teeth members 244 extendthrough an opening of the handpiece 202 that is in communication withthe slot 236. The gear 234 of the coupling member 228 is disposed withinthe slot 236.

A depression 247 extends proximally from the slot 236 within thehandpiece 202. The depression 247 is configured to receive both theextension member 239 of the coupling member 228, as well as the hubelement 235. The extension member 239 is configured to be at leastpartially disposed within the depression 247 to maintain the couplingmember 228 within the slot 236 of the handpiece 202.

First actuation member 204 is pivotally attached to a portion of handle202 such that it is adjacent to rotation wheel 206. In one exemplaryconfiguration a torsional spring (not shown) is engaged at a pivot pointA to bias first actuation member 204 into a ready position, namely aposition whereby the proximal end 248 of the first actuation member 204biased upwardly from an outer surface of the handpiece 202. In anotheralternative arrangement, a coil spring (not shown) is disposed withinthe cavity 230 to affect the biasing force on the first actuation member204. When the first actuation member 204 is activated against thebiasing force F created by the spring, inner cannula 208 may be advancedforward. This action causes second jaw member 229 to move toward firstjaw member 221 within a slot 250 formed in the cap member 220. Morespecifically, actuation of the first actuation member 204 will causecoupling member 228 to slide forward within the cavity formed by the webmember 240 and rotational wheel 206. Because the proximal end of theinner cannula 208 is fixedly connected to the coupling member 228, asthe coupling member 228 moves, inner cannula 208 will also move.

Further, to maintain the opposing gripping surface orientation of thefirst and second jaw members 221, 229, the distal extension member 242may be operatively connected to the rotation wheel 206 with a splinedconnection. In another exemplary arrangement, the distal extensionmember 242 may be a hexagonal cross-section that cooperates with amating hexagonal opening formed through the rotation wheel 206. Othercross-sectional shapes with corresponding mating openings are alsocontemplated. With either of these configurations, the inner cannula 208and the center wire 212 will be rotationally fixed with the rotationwheel 206 such that as rotation wheel 206 rotates, center wire 212 andinner cannula 208 will also rotate. However, the splined connection ormating configuration will enable inner cannula 208 to slide axially,independent of rotation wheel 206.

As the first actuation member 204 is depressed, the inner cannula 208will traverse the slot 250 formed in the cap member 220, causing thesecond jaw member 229 to move toward the first jaw member 221, and inparticular the gripping surface 233 to more toward gripping surface 223.Any tissue or vessels that are positioned between the first and secondjaw members 221, 229 as inner cannula 208 is actuated, will be gripped.Continued depression of first actuation member 204 will maintain thesecond jaw member 229 against the first jaw member 221.

Because the first and second actuation members 204, 206 are positionedadjacent one another, a user may easily rotate inner cannula 208 andcenter wire 212 to reposition the distal end of the instrument 200, aswell as advance (and retract) inner cannula 208 with a single hand andwithout requiring removal of the surgical instrument 200 from thesurgical site. This configuration allows for reduced visibilityconcerns, and permits the user to select and maintain an optimal siteline, without requiring a user to manually rotate the entire instrumentto achieve a desired surgical technique. Further, because the first andsecond actuation members may be easily activated with a single hand, thesecond hand is free to handle other surgical instruments that may benecessary during a given procedure.

An alternative arrangement of a second actuation mechanism 306 that maybe utilized with either of microsurgical instruments 100 or 200 is shownin FIGS. 12-14. The second actuation mechanism 306 replaces the rotationwheel 106 and 206 found in instruments 100 and 200.

Second actuation mechanism 306 comprises a first gear wheel 305, asecond gear wheel 307 and a third gear wheel 309. Each of the respectivegear wheels 305, 307, and 309 include a plurality of gear teeth 311disposed about their respective peripheries. The gear teeth 311 of eachof the respective gear wheels 305, 307 and 309 are configured to meshtogether in an operative fashion. All of the gear wheels 305, 307, and309 are also mounted for rotational movement, as will be discussed infurther detail below.

The handpiece 302, to which the gear wheels 305, 307, and 309 areoperatively mounted, includes a first mounting yoke 313 that ispositioned adjacent the first actuation mechanism 304. The firstmounting yoke 313 extends outwardly from an outer periphery of thehandpiece 302, as best seen in FIGS. 12-13. The first mounting yoke 313includes first and second wall members 315 a, 315 b that are arranged inan opposing manner so as to define a channel therebetween. Each of thewall members 315 a, 315 b includes an aligned opening 319 a, 319 b intowhich a rod member (not shown may be inserted. In one exemplaryarrangement, the first mounting yoke 313 may be integrally formed withhandpiece 302. Alternatively, the first mounting yoke 313 may beseparately secured to the handpiece 302. The first gear wheel 305 ispositioned in the channel between the first and second wall members 315a, 315 b. The rod member is inserted within the openings 319 a, 319 b,as well as through an opening 317 (best seen in FIG. 14) formed throughthe first gear wheel 305. The first gear wheel 305 is configured to befreely rotatable about the rod member.

The second gear wheel 307 is arranged along a common plane 14-14 withfirst and third gear wheels 305 and 309. The second gear wheel 307 isalso mounted on a second mounting yoke 321. Second mounting yoke 321 isconstructed in a similar fashion as the first mounting yoke 313 andincludes first and second wall members (only second wall member 323 bvisible) that are arranged in an opposing manner with a channeltherebetween. The second yoke member 321 extends radially outwardly froman outer periphery of the handpiece 302. The second gear wheel 307 ispositioned with the second yoke 321 and a rod is inserted throughaligned openings 325 b and an opening 327 of the second gear wheel 307.

As may be best seen in FIG. 14, an inwardly extending groove 329 isformed in the handpiece 302. The groove 329 is in communication with acavity 330 formed within the handpiece 302 into which the third gearwheel 309 is disposed. The groove 329 serves to position the second gearwheel 307 partially in the handpiece 302 and in meshing engagement withthe first and third gear wheels 305 and 309.

Referring to FIG. 13, the handpiece 302 includes a cavity 330. Cavity330 includes first, second and third cavity portions 330 a, 330 b, 330c. The second cavity portion 330 b is positioned between the first andthird cavity portion 330 a, 330 c and has a length that is larger thanthe first and third cavity portions 330 a, 330 c. The third gear wheel309 is positioned within the second cavity portion 330 b. The secondcavity portion 330 b is in communication with the groove 329. The thirdcavity portion 330 c is in communication with a slot 334 into which acoupling member 328 is positioned. The slot 334 has an opening throughthe handpiece 302 in a similar fashion as that previously described inconnection with instruments 100/200.

The coupling member 328 is similar to those described above inconnection with instruments 100/200. More specifically, the couplingmember 328 includes a gear mechanism 334, as well as a distal end thatincludes an engagement section 335. In the exemplary arrangement shown,the engagement section 335 is configured with a hexagonal shape thatmatingly engages a corresponding opening 337 formed in the third gearwheel 309. With this arrangement, coupling member 328 is able to slideaxially within the third gear wheel 309. However, because the engagementsection 335 is disposed within the third gear wheel 309, when the thirdgear wheel 309 rotates, the coupling member 328 will also rotate. Thecoupling member 328 has an inner cannula 308 that is fixedly mounted tothe coupling member 328 in the manner described above in connection withinstruments 100/200.

The first actuation member 304 includes teeth members 344 thatoperatively engage with gear mechanism 334 of the coupling member 328.The first actuation member 304 is pivotally attached to a portion ofhandpiece 302 such that it is adjacent to the second actuation member306. In one exemplary configuration a torsional spring (not shown) isengaged at a pivot point A to bias first actuation member 304 into aready position, namely a position whereby the proximal end 348 of thefirst actuation member 304 is biased upwardly from an outer surface ofthe handpiece 302. Further, as an alternative arrangement, a coil spring(not shown) may be disposed within the cavity 320 to bias the firstactuation member 304. When the first actuation member 304 is activatedagainst a biasing force created by the spring, the interaction betweenthe teeth members 344 and the gear mechanism 334 cause the couplingmember 328 to move forward. Because the inner cannula 308 is fixedlymounted to the coupling member 328, the inner cannula 308 is also movedforward.

Even while advancing the inner cannula 308 by actuating the firstactuation member 304, it is possible to selectively rotate the innercannula 308, as well. More specifically, while one finger is depressingthe first actuation member 304, a second finger may be used toselectively rotate the first gear wheel 305. This action will cause thesecond gear wheel 307 to rotate, due to the intermeshed teeth 311 of thefirst and second gear wheels 305 and 307, respectively. Once the secondgear wheel 307 rotates, the third gear wheel 309 will rotate due to theintermeshing of the teeth 311 of the second and third gear wheels 307,309. Because the engagement section 335 of the coupling member 328 isdisposed within the third gear 309, rotation of the third gear wheel 309causes the coupling member 328 to rotate. Moreover, because the innercannula 308 is fixedly connected to the coupling member 328, rotation ofthe coupling member 328 causes the inner cannula 308 to also rotate.

FIG. 15 illustrates a further embodiment of a microsurgical instrument400.

Instrument 400 has basically the same structure as has been describedabove in connection with instruments 100/200. More specifically,instrument 400 includes a handpiece 402 to which inner and outercannulas 408, 410, respectively are operatively connected. A couplingmember 428 is disposed within the handpiece 402, as is a hub 426. Theinner cannula 408 a (shown in FIGS. 16-17), 408 b (shown in FIGS. 18 and20) has a proximal end that is fixed to the coupling member 428 in asimilar manner as has already been described in connection withinstruments 100/200. The outer cannula 410 is fixed to the hub 426 suchthat the outer cannula 410 may rotate, but not translate. Further,because hub is operatively connected to the coupling member 428, theouter cannula 410 is rotationally fixed with the inner cannula 408.

Referring to FIGS. 16-17 on exemplary arrangement of a distal end 401 ofinstrument 400 will now be described. Inner cannula 408 a is disposedwithin outer cannula 410 a. Inner cannula 408 a may be generally hollow,as depicted, or formed as a solid piece through most of its length. Asmay be seen in FIG. 16, a portion of a distal end of the inner cannula408 a is removed, leaving a land member 411. Connected to a distal endof the land member 411 is a toe portion 413. Toe portion 413 comprises aportion of the side wall of the inner cannula 408 a and is disposed onone side of the land member 411. A distal edge 415 may be sharpened ifthe instrument is desired to be used as a cutting device. A bottom edge417 of the distal end of the inner cannula 408 a may be beveled toprovide for effective sliding relationship between the inner cannula 408a and the outer cannula 410 a. The wall of the inner cannula 408 aadjacent the land member 411 may be beveled toward the land member 411to provide for improved line of sight.

The outer cannula 410 a is generally hollow, as well. A portion of thedistal end of the outer cannula 410 a is also removed, leaving a landmember 419. Connected to a distal end of the land member 419 is a toeportion 421. Toe portion 421 comprises a portion of the side wall of theouter cannula 410 a and is disposed on the same side of the land member419 of the outer cannula 410 a as the toe portion 413 of the innercannula 408 a. A proximal edge 423 may be sharpened if the instrument isdesired to be used as a cutting device. The wall of the outer cannula410 a adjacent the land member 419 may be beveled toward the land member419 to provide for improved line of sight of the distal end 401 of theinstrument. In one exemplary arrangement, the toe portion 421 of theouter cannula 410 a may be provided with a height H₁ that is longer thanthe height H₂ of the toe portion 413 of the inner cannula 408 a. Thiswill also serve to provide an improved line of sight during a procedure,as well as allow for effective manipulation of tissue.

In operation, the outer cannula 410 a is fixed against axial movement,but may rotate in response to activation of the second actuation member406 (along with inner cannula 408 a). The inner cannula 408 a may beselectively advanced to bring the respective toe portions 413, 421 ofthe inner and outer cannula 408 a, 410 a together. More specifically,actuation of the first actuation member 404 will cause the couplingmember 428 to advance distally. As the coupling member 482 carries theinner cannula 408 a, the toe portion 413 of the inner cannula 408 a willmove toward the toe portion 421 of the outer cannula 410 a. If the edges415 and 423 are configured as sharpened edges, the actuation of thefirst actuation member 408 a will achieve a cutting action. If the edges415 and 423 are not configured with a sharpened edge, the interaction ofthe inner and outer cannulas 408 a, 410 a will operate as a graspingdevice.

A further alternative arrangement of a distal end 401 of instrument 400will now be described in connection with FIGS. 18-20. Inner cannula 408b is configured to be disposed within outer cannula 410 b. Inner cannula408 b may be generally hollow, as depicted, or formed as a solid piecethrough most of its length. As may be seen in FIG. 18, a portion of adistal end of the inner cannula 408 b is removed, leaving a land member411. Connected to a distal end of the land member 411 is a toe portion413. Toe portion 413 comprises a portion of the side wall of the innercannula 408 b and is disposed on one side of the land member 411. Adistal edge 415 may be sharpened if the instrument is desired to be usedas a cutting device. While not shown, it is understood that the wall ofthe inner cannula 408 b adjacent the land member 411 may be beveledtoward the land member 411 to provide for improved line of sight.

The outer cannula 410 b is generally hollow, as well. A portion of thedistal end of the outer cannula 410 b is also removed, leaving a landmember 419. Connected to a distal end of the land member 419 is a toeportion 421. Toe portion 421 comprises a portion of the side wall of theouter cannula 410 b and is disposed on the same side of the land member419 of the outer cannula 410 b as the toe portion 413 of the innercannula 408 b. A proximal edge 423 may be sharpened if the instrument isdesired to be used as a cutting device. The wall of the outer cannula410 b adjacent the land member 419 may be beveled toward the land member419 to provide for improved line of sight of the distal end 401 of theinstrument. In one exemplary arrangement, the toe portion 421 of theouter cannula 410 b may be provided with a height that is longer thanthe height of the toe portion 413 of the inner cannula 408 b. This willalso serve to provide an improved line of sight during a procedure, aswell as allow for effective manipulation of tissue.

In operation, the outer cannula 410 b is fixed against axial movement,but may rotate in response to activation of the second actuation member406 (along with inner cannula 408 b). The inner cannula 408 b may beselectively advanced to bring the respective toe portions 413, 421 ofthe inner and outer cannula 408 a, 410 a together, as is shown in FIG.20. More specifically, actuation of the first actuation member 404 willcause the coupling member 428 to advance distally. As the couplingmember 482 carries the inner cannula 408 b, the toe portion 413 of theinner cannula 408 b will move toward the toe portion 421 of the outercannula 410 b, as the inner cannula 408 b is nested within the outercannula 410 b. If the edges 415 and 423 are configured as sharpenededges, the actuation of the first actuation member 408 a will achieve acutting action. If the edges 415 and 423 are not configured with asharpened edge, the interaction of the inner and outer cannulas 408 a,410 a will operate as a grasping device.

Referring to FIG. 20, in one exemplary arrangement, a distal edge 425may be rounded to remove a sharp corner, thereby lessening potentialtissue damage during operation. Further the distal edge 415 of the innercannula 408 b may be configured to be disposed at a more vertical anglethan a coincident point of the outer cannula 410 b. This configurationpermits a heavy bias to be introduced to the toe portions 413, 421 tocause the toe portions 413, 421 to rub together without getting caughton each other during repeated actuations.

The land members 411/419 and toe portions 413/421 of the inner and outercannulas may be constructed using a series of planar wire EDM cuts. Inone exemplary arrangement, the wire used for the inner and outercannulas may be subjected to a first cut operation and then the tubingis rotated 90 degrees for a second cut to achieve a configuration thatmay be flattened out into the desired final toe portion shape.

Another exemplary embodiment is illustrated in FIGS. 21-23.Microsurgical instrument 500 comprises a handpiece 502, a firstactuation member 504, a second actuation member 506, an inner cannula508 (as shown in FIGS. 22 and 23), an outer cannula 510, a center wire512 (as shown in FIGS. 22 and 23), and a stationary cannula 513. Thehandpiece 502 may be generally curvilinear forming a shape configured tocomfortably fit a surgeon's hand. As shown in FIG. 21, the handpiece 502may define an indent 515 on an underside of the handpiece 502. Aproximal end 514 may be curved upward to fit the palm of a hand. Thehandpiece 502 may define a cavity 530 (as best shown in FIGS. 22 and 23)housing at least a portion of the first actuation member 504, the secondactuation member 504, a coupler 550, a connector 570, the inner cannula508, the outer cannula 510, the center wire 512, and the stationarycannula 513.

The outer cannula 510 is defined by a distal end 516 and a proximal end518 (best seen in FIGS. 21 and 23, respectively). The proximal end 518is fixed within the coupler 550, as shown in FIGS. 22 and 23.

The outer cannula 510 may be maintained at a distal end of the handpiece502 by the stationary cannula 513, which may be fixed to a portion ofthe interior of the handpiece 502 via any suitable manner, such as glue,welding, etc. The outer cannula 510 may be movable within the stationarycannula 513, which may act as a guide for the wire 512 and the outercannula 510. The stationary cannula 513 may include an offset bend (asillustrated in FIG. 21) that allows for a clear line of sight during theprocedure. The stationary cannula 513 may be configured to beselectively malleable such that the stationary cannula 513 may be bentto a desired configuration and maintained in the desired position untilbent otherwise. The outer cannula 510 may be maintained within thestationary cannula 513 and thus bendable with the stationary cannula513. The stationary cannula 513 may extend over a large enough portionof the outer cannula 510 so as to force the outer cannula 510 to bend.

The inner cannula 508 is received within the outer cannula 510. Theouter cannula 510 is operatively connected to the second actuationmember 506. In one exemplary configuration, the second actuation member506 is configured as a rotation wheel 506. Thus, when rotation wheel 506is rotated, outer cannula 510 also rotates.

The center wire 512 is positioned within the inner cannula 508. Muchlike the arrangement of microsurgical instrument 100 depicted in FIG. 3,the center wire 512 may include one or more relief cut-outs to allow forflexibility while providing for columnar strength, similar to thoseshown with respect to relieve cut-outs 125 of inner cannula 108.

As shown best in FIG. 23, the first actuation member 504 may be a lever504 configured to engage the coupler 550. The coupler 550 includes atleast two stoppers 554, forming a dog-bone type of shape. The thumblever 504 is arranged between the two stoppers 554. The coupler 550 maydefine a coupler channel 552 wherein the center wire 512 extends therethrough. The center wire 512 may be fixed to the sides of the channel552 and upon actuation of the thumb lever 504, the wire 512 may be movedforward or backward. The movement of the wire 512 may counter themovement of the lever 504. For example, if the lever 504 is pulled backtoward the user, the coupler 550 and the wire 512 may move forward andif the lever 504 is pushed forward away from the user, the coupler 550and the wire 512 may move backward. The movement of the wire 512 mayultimately control a blade 582 at the distal end of the outer cannula510, as discussed below.

The lever 504 may include a handle 556 arranged on the outside of thehandpiece 502 and a pivot point 560 arranged inside the handpiece 502.The handle 556 extends proximally from a slot 536 within the handpiece502 and is configured to move the lever 504 between a forward positionand backwards position. The lever 504 may be biased in some form so asto be maintained in the forward, or ready, position. That is, when notactuated, the lever 504 will maintain the center wire 512 in a ready,un-actuated position. The biasing may be accomplished by a coil spring(not shown). Thus, by actuating the lever 504 against the biasing forcecreated by the spring, the coupler 550 is slid forward, thus moving thewire 512 forward.

As explained, the second actuation member 506 may be a rotation wheel506, similar to rotation wheel 106, configured to rotate the outercannula 510 as well as the inner cannula 508 and center wire 512.

The cavity 530 defined by the handpiece 502 may include a first portion530 a configured to receive a first hub member 526 of the secondactuation member 506. The first hub member 526 may maintain the secondactuation member 506 within the cavity 530 a, similar to hub members 126and 226 described above. The cavity 530 may also include a secondportion 530 b and a third portion 530 c. The second portion 530 b isdesigned to receive the wheel 506 and the third portion 530 c isdesigned to receive a second hub member 527, a portion of the connector570, the coupler 550, and the first actuation member 504. The second hubmember 527 may be similar to the first hub member 526 in that it may beconfigured to maintain the wheel 506 within the handpiece 502 whilestill allowing the wheel 506 to rotate within the second portion 530 b.The hub members 526, 527 may be made of compliant material having somememory that may be selectively deformed as the hub members 526, 527 arepress-fit into the first and second portions 530 a, 530 c. For example,once the second hub member 527 enters the third portion 530 c of thecavity 530, the second hub member 527 will return to its original shape,thereby being trapped within the third portion 530 c.

The second actuation member 506, or wheel 506, may define a wheel cavity558 extending from the near-center of the wheel within the secondportion 530 b of the cavity 530 through the second hub member 527 andopen to the third portion 530 c. The wheel cavity 558 may be configuredto receive a portion of the connector 570 and may be defined to mimicthe outer shape of the connector 570. In one exemplary configuration,the connector 570 is a hexagonal prism and the wheel cavity 558 is alsoformed in a similar shape so that the sides of the cavity 558 may acceptand interlock with the connector 570. Thus, when the wheel 506 rotates,so does the connector 570. Notably, the connector 570 may be any shapeand is not limited to a hexagonal periphery.

The distal end of the connector 570 may be configured to reside withinthe wheel cavity 558 and may be fixed to the wheel cavity 558 via glue,or some other mechanism to increase the durability of the fit therein.The connector 570 receives the coupler 550 at the proximal end. That is,the distal end 562 of the coupler 550 may fit within the connector 570,as shown in FIG. 23. The distal end 562 of the coupler may also mimicthe shape of the connector 570. Thus, when the wheel 506 rotates, sodoes the connector 570 and subsequently so does the coupler 550.Additionally, the coupler 550 may move laterally within the connector570 to account for the movement of the coupler 550. For example, whenthe first actuation member 504 is depressed and the coupler 550 is movedforward, the connector 570 has enough room to accept the forward movingcoupler 550 so as to not disturb the functions of the second actuationmember 506. Thus, the connector 570 translates rotation of the wheel 506to the coupler 550, while still allowing lateral movement of the coupler550 so that the wire may simultaneously move laterally and rotationally.While the connector 570 is shown as a separate element, the connector570 may be integrated with and molded as a feature of the wheel 506.

The outer cannula 510 may extend through the first portion 530 a andsecond portion 530 b of the cavity 530, specifically through the wheel506 and stationary cannula. The outer cannula 510 may be fixed to thewheel 506 so as to rotate as the wheel 506 is rotated by the user. Thecenter wire 512 is fixed to the coupler 550 so as to move with thecoupler 550, as dictated by the lever 504.

The outer cannula 510 and stationary cannula 513 may extend from thehandpiece 502 at the distal end. As explained, the stationary cannula513 may be malleable and bent to a desired configuration. As shown inFIGS. 24-26, the distal tip of the outer cannula 510 includes a cuttingmechanism 580. The cutting mechanism 580 may include a blade 582 and acut block 584. A cap member 586 may be arranged on the distal end of theouter cannula 510. The cap member 586 may have a larger diameter thanthat of the outer cannula 510. The cap member 586 may be attached to theouter cannula 510 via a welded joint.

The blade 582 is affixed to the center wire 512 and extends out of aslot 590 in the cap member 586. An opening 596 is defined between theblade 582 and the cut block 584, when the blade 582 is in the readyposition. The blade 582 may be similar to cutting edge 131 describedabove. If the wire is moved forward at the handpiece 502 by actuation atthe lever 504, the blade 582 traverses the slot 590. Any tissue orvessels that are positioned within the opening 596 as the blade 582 istraversed will be cut. A full depression of the lever 504 will cause theblade 582 to engage and abut the cut block 584. Continued depression ofthe first actuation member 504 will maintain the blade 582 against thecut block 584. This action may be desired when withdrawing theinstrument 500 from a surgical site so as not to unintentionally rakethe opening 596 against any tissue. It may also be desirable to have theblade 582 in engagement with the cut block when rotation of the distalend of the inner cannula 508 is desired.

As shown in the example in FIG. 24, the cut block 584 may form atear-drop like shape such that the tip of the tear-drop is configured toact as a stop for the blade 582. The cut block 584 is maintained on thedistal end of the cap member 586. The cut block 584 may be constructedout of material that is compliant, such that engagement of the blade 582with the cut block 584 will not damage the blade 582. The cut block 584may be fixedly connected to the cap member 586. In another exemplaryconfiguration, as shown in FIG. 25, the cut block 584 may define a cutblock recess 592. The recess 592 may be configured to receive the blade582 as the blade 582 moves forward through the slot 590. The recess 592may extend through the entire cut block 584 such that the blade 582 maypass through the cut block 584 in its entirety. The recess 592 may alsoform a partial cut-out within the cut block 584 where the cut block 584is solid at the distal end, thus preventing the blade 582 fromcompletely passing through the cut block 584. By permitting the blade582 to pass through the recess 592, the tissue held between the bladeand recess 592 may eventually be stretched and severed in a scissor-likefunction.

FIG. 26 illustrates another exemplary cut block 684 wherein the cutblock 584 includes a pair of cut block blades 594 defining apass-through there between. The blade 582 may be pushed through the cutblock blades 594. The cut block blades 594 may define a small openingbetween them in order to create a frictional fit around the blade 582.The cut block blades 594 thus create a biasing against the blade 582 tofacilitate severing of the tissue. The cut block 684 may include a keyguide 688 configured to act as a guide for the inner cannula 508. Thatis, as the inner cannula 508 moves towards the distal end of the outercannula 510 and cap member 586, the inner cannula 508 may engage the keyguide 688. The key guide 688 may aid in reducing rotation of the innercannula within the cap 586.

FIG. 27 illustrates a cross-sectional view of the distal end of themicrosurgical instrument 500. In the example shown, the inner cannula508 and outer cannula 510 may define an opening 596 allowing the blade582 connected to the wire 512 to extend there through.

Accordingly, because a handpiece includes first and second actuationmembers that are positioned adjacent one another, a user may easilyrotate inner cannula and center wire to reposition the distal end of theinstrument, as well as advance (and retract) inner cannula with a singlehand and without requiring removal of the surgical instrument from thesurgical site. This configuration allows for reduced visibilityconcerns, and permits the user to select and maintain an optimal siteline, without requiring a user to manually rotate the entire instrumentto achieve a desired surgical technique. Further, because the first andsecond actuation members may be easily activated with a single hand, thesecond hand is free to handle other surgical instruments that may benecessary during a given procedure.

It will be appreciated that the surgical instrument and methodsdescribed herein have broad applications. The foregoing embodiments werechosen and described in order to illustrate principles of the methodsand apparatuses as well as some practical applications. The precedingdescription enables others skilled in the art to utilize methods andapparatuses in various embodiments and with various modifications as aresuited to the particular use contemplated. In accordance with theprovisions of the patent statutes, the principles and modes of operationof this disclosure have been explained and illustrated in exemplaryembodiments.

It is intended that the scope of the present methods and apparatuses bedefined by the following claims. However, it must be understood thatthis disclosure may be practiced otherwise than is specificallyexplained and illustrated without departing from its spirit or scope. Itshould be understood by those skilled in the art that variousalternatives to the embodiments described herein may be employed inpracticing the claims without departing from the spirit and scope asdefined in the following claims. The scope of the disclosure should bedetermined, not with reference to the above description, but shouldinstead be determined with reference to the appended claims, along withthe full scope of equivalents to which such claims are entitled. It isanticipated and intended that future developments will occur in the artsdiscussed herein, and that the disclosed systems and methods will beincorporated into such future examples. Furthermore, all terms used inthe claims are intended to be given their broadest reasonableconstructions and their ordinary meanings as understood by those skilledin the art unless an explicit indication to the contrary is made herein.In particular, use of the singular articles such as “a,” “the,” “said,”etc. should be read to recite one or more of the indicated elementsunless a claim recites an explicit limitation to the contrary. It isintended that the following claims define the scope of the invention andthat the method and apparatus within the scope of these claims and theirequivalents be covered thereby. In sum, it should be understood that theinvention is capable of modification and variation and is limited onlyby the following claims.

While exemplary embodiments are described above, it is not intended thatthese embodiments describe all possible forms of the invention. Rather,the words used in the specification are words of description rather thanlimitation, and it is understood that various changes may be madewithout departing from the spirit and scope of the invention.Additionally, the features of various implementing embodiments may becombined to form further embodiments of the invention.

What is claimed is:
 1. A surgical instrument, comprising: a housing; afirst actuation member configured; a coupler operatively connected tothe first actuation member for imparting a reciprocating action to aportion of the instrument; a second actuation member configured forimparting a rotational action to a portion of the instrument; a firstcannula operatively connected to the second actuation member, such thatthe first cannula is configured for rotational movement with respect tothe housing, and a wire member at least partially disposed within thefirst cannula and fixed to the coupler, the wire member configured torotate and reciprocate with the coupler.
 2. The surgical instrument ofclaim 1, wherein the first cannula further comprises a cut blockdisposed at a distal end thereof.
 3. The surgical instrument of claim 1,wherein the wire member includes a cutting member at a distal endthereof.
 4. The surgical instrument of claim 3, further comprising a capmember arranged on a distal end of the first cannula, the cap memberdefining a slot configured to receive the cutting member.
 5. Thesurgical instrument of claim 4, wherein the wire member is operativelyconnected to the first actuation member to selectively reciprocate thecutting member across the slot upon actuation of the first actuationmember.
 6. The surgical instrument of claim 1, wherein the firstactuation member is positioned adjacent to the second actuation member.7. The surgical instrument of claim 1, wherein the coupler isoperatively connected to the second actuation member via a connector andwherein the second actuation member is configured to impart therotational action to the connector and the coupler.
 8. The surgicalinstrument of claim 1, wherein the first actuation member furthercomprises a lever member that is arranged between a pair of stoppingmembers of the coupler and configured to laterally move against at leastone of the stopping members to move the coupler based on a force at thelever member.
 9. The surgical instrument of claim 1, wherein the secondactuation member further comprises a rotation wheel that is fixed to aportion of the first cannula such that actuation of the rotation wheelcauses the first cannula to rotate.
 10. The surgical instrument of claim1, wherein the wire member is fixedly connected to the coupler such thatthe first cannula and the wire member are rotationally fixed withrespect to one another.
 11. The surgical instrument of claim 1, furthercomprising a second cannula disposed over the first cannula, wherein thesecond cannula is fixedly connected to the housing.
 12. The surgicalinstrument of claim 11, wherein the second cannula is selectivelymalleable.
 13. A surgical instrument, comprising: a housing; a firstactuation member configured for imparting a reciprocating action to awire member; a second actuation member configured for imparting arotational action to a first cannula; a cap member arranged at a distalend of the first cannula, wherein the cap member defines a slotconfigured to receive a blade; and wherein reciprocation of the wiremember causes the blade to move transversely across the slot to severtissue elements.
 14. The surgical instrument of claim 13, furthercomprising a cut block arranged at the distal end of the first cannulawhereby upon reciprocation of the wire member, the bade is brought intoengagement with the cut block.
 15. The surgical instrument of claim 14,wherein the cut block defines a recess configured to receive at least aportion of the blade in response to reciprocation of the wire member.16. The surgical instrument of claim 14, wherein the cut block includesa pair of cut blocks defining an opening there between to receive atleast a portion of the blade in response to reciprocation of the wiremember.
 17. The surgical instrument of claim 14, wherein the wire memberand the first cannula are configured to rotate together in response torotational action at the second actuation member.
 18. The surgicalinstrument of claim 14, further comprising a second cannula configuredto surround at least a portion of a length of the first cannula.
 19. Thesurgical instrument of claim 18, wherein the second cannula isconfigured to be malleable whereby the first cannula and the wire membertherein are moveable within the second cannula.
 20. The surgicalinstrument of claim 18, wherein the first cannula remains stationarywith respect to the second cannula upon rotation of the second cannula.